This section provides background information to facilitate a better understanding of the various aspects of the disclosure. It should be understood that the statements in this section of this document are to be read in this light, and not as admissions of prior art.
Natural gas fueled well operation technology has gained wide acceptance in the industry. Moreover, certain leaders in the industry have further designed, built and commissioned natural gas mobile facilities, including mobile storage and vaporization trailers and pipeline components, to provide the natural gas fuel to the natural gas fueled engines, on site. In this manner, it is now accepted practice to run well operation equipment, including fracturing and drilling equipment, on natural gas, and to thereby realize a significant savings in fuel cost, over the former practice of using diesel fuel while also reducing NOx and particulate emissions.
Equipment at a well being fractured requires large amounts of fuel. Conventionally, if the equipment needs to be at the well site during a very large fracturing job, the fuel tanks of the equipment may need to be filled up several times, and this is done by the well known method of manually discharging fluid from a fuel source into each fuel tank one after the other. If one of the fuel tanks runs out of fuel during the fracturing job, the fracturing job may need to be repeated, or possibly the well may be damaged. The larger the fracturing job, the more likely equipment is to run out of fuel. Dangers to the existing way of proceeding include: extreme operating temperatures and pressures, extreme noise levels, and fire hazard from fuel and fuel vapors.
Polymer hosing is used to connect the natural gas fueled engines and the natural gas mobile storage and vaporization equipment. The presently accepted practice, in the industry, is to assemble and run a 7.62 cm diameter poly hose structure from the natural gas mobile storage and vaporization equipment supply trailer to well operation equipment. However, at extremely low temperatures such as −20 deg C. or lower, conventional polymer hosing is prone to ultimately crack and fail given the conditions they are exposed to.
Epichlorohydrin rubber (ECO) has very low glass transition temperature (Tg), excellent fuel permeation resistance and a saturated polymer backbone, and has such, it has been used in fuel hoses for low temperature resistance, fuel permeation resistance and ozone resistance especially in “dry out” applications where limited amount of plasticizer is allowed in the formulation. In dry out applications, the fuel will be “dried out” from hoses after each service use, which makes hose tube exposed prone to ozone attack. Plasticizers will also be extracted out by fuels after a short period of time, which also, decreases low temperature flexibility.
However, ECO, used alone, does not have sufficient ‘green strength’ during hose manufacture. Green strength is required for non-mandrel extrusion processes, especially for large diameter hoses. NBR/PVC alloy has also been used in fuel hose for low temperature resistant, fuel permeation resistant fuel and ozone resistance, but it cannot achieve both acceptable low temperature resistance and good fuel permeation resistance, especially in the “dry out” applications.
Hence, it is desirable to have hoses for transferring fluids, which have sufficient properties, “dry out” application capability, flexibility, and long term durability under extremely low temperature conductions, such need met, at least in part, with embodiments according to this disclosure.